966 resultados para energy performance


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There are 3 distinct yet closely integrated processes that operate together to satisfy the energy requirements of muscle. The anaerobic energy system is divided into alactic and lactic components, referring to the processes  involved in the splitting of the stored phosphagens, ATP and  phosphocreatine (PCr), and the nonaerobic breakdown of carbohydrate to lactic acid through glycolysis. The aerobic energy system refers to the combustion of carbohydrates and fats in the presence of oxygen. The anaerobic pathways are capable of regenerating ATP at high rates yet are limited by the amount of energy that can be released in a single bout of intense exercise. In contrast, the aerobic system has an enormous capacity yet is somewhat hampered in its ability to delivery energy quickly. The focus of this review is on the interaction and relative contribution of the energy systems during single bouts of maximal exercise. A particular emphasis has been placed on the role of the aerobic energy system during high intensity exercise.

Attempts to depict the interaction and relative contribution of the energy systems during maximal exercise first appeared in the 1960s and 1970s. While insightful at the time, these representations were based on calculations of anaerobic energy release that now appear questionable. Given repeated reproduction over the years, these early attempts have lead to 2 common misconceptions in the exercise science and coaching professions. First, that the energy systems respond to the demands of intense exercise in an almost sequential manner, and secondly, that the aerobic system responds slowly to these energy demands, thereby playing little role in determining performance over short durations. More recent research suggests that energy is derived from each of the energy-producing pathways during almost all exercise activities. The duration of maximal exercise at which equal contributions are derived from the anaerobic and aerobic energy systems appears to occur between 1 to 2 minutes and most probably around 75 seconds, a time that is considerably earlier than has traditionally been suggested.

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Concern about the growth of greenhouse gas emissions in Victoria has prompted the introduction of legislation to improve the thermal performance of the residential building envelope. Unfortunately, the size of the house is not considered in the rating tool that underpins the legislation. The energy embodied in the constructional materials is also not considered although it too is directly related to the size of the house. Another intrinsic factor relating residential housing energy and greenhouse gas emissions is the location of the residence and the travel preferences of the homeowner. The relationship between the operational, embodied and travel energy associated with a typical residential scenario in Melbourne over the last 50 years is examined in this paper. The analysis found that by the year 2000, the energy associated with work-related travel (44%) now exceeds the operational energy (37%). In terms of greenhouse gas emissions, the contribution from travel energy is almost double that from operational energy (28%).

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Performance of advanced fabric energy storage systems has not been reported for Australian conditions. The influence pf slab thickness and air flow rate on the annual thermal load, and maximum heating and cooling demands for a typical office module using a ventilated hollow core concrete slab system has been investigated by simulation. Performance results for Melbourne are presented and comments made on other locations.

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Fabric energy storage (FES) systems have gained in popularity in the recent years in response to the demand for energy efficient buildings. The dynamic heat transfer mechanisms of an FES require specialised techniques to predict its thermal performance. This requirement has been one of the barriers to the wider use of FES systems. Based on the research literature, this paper presents a critical review of the published mathematical models of FES systems. The paper discusses the usefulness of these models based on the following criteria: the inputs required; the accuracy of predictions; the ability to link with commercially available simulation software: and the degree of difficulty in using the models. The review found that the currently available mathematical models are either not able to predict the thermal behaviour of a building space with an FES system reliably or the models are too complicated and/or require too much specialised knowledge to make them useful.

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The operation of two 60 m2 solar air heaters serving a large studio teaching space has been monitored for a twelve month period. The solar contribution of the heaters was found to be less than 5%, and in some instances the heaters actually contributed to the space heating load. A validated mathematical model of the studio and it’s heating, ventilation and air conditioning system was used to investigate performance improvement strategies. It was found a different control strategy and recommissioned control sensors would substantially improve the solar air heater performance.

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The effects of a commercial sports drink on performance in high-intensity cycling was investigated. Nine well-trained subjects were asked to complete a set amount of work as fast as possible (time trial) following 24 h of dietary (subjects were provided with food, energy 57.4 ± 2.4 kcal/kg and carbohydrate 9.1 ± 0.4 g/kg) and exercise control. During exercise, subjects were provided with 14 mL/kg of either 6% carbohydrate-electrolyte (CHO-E) solution or carbohydrate-free placebo (P).

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This thesis describes the exploration and the development of computational means to investigate the behaviour of design objects before they are available for investigation in the physical world. The motivation is to inform the design process about the design object's performance in order to achieve better--more performance-oriented--design outcomes in the sense of energy efficiency and comfort performance than can be achieved by conventional design techniques.

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This paper describes a recent performance work I made using dance and live feed video
processing, 1 + x: mid-range projections, commissioned by the Seoul Contemporary Dance
Company and first performed in Melbourne in July 2005. This work forms a basis for discussing
my interest in creating performance images that reveal 'interiority'. I am interested in how you
embed the 'feel' of the human systematically in an interactive structure, and how that process
can produce a poetic that arises from the detailed and nuanced play between real and virtual
images on the same screen. How do you abstract and play with a performer's movement, play
with it in real and virtual time, so that it gives the work an emotional charge? Its like playing with
the process of 'becoming virtual' - and I'm being deliberately Deleuzian about that - how do you
'become virtual' in the sense of melding performer and image so that the meaning exists
between - in the connection between the two?

This quest to get the energy, the 'lived', 'felt' quality of the movement into the imagery gives rise
to research questions about how 'presence' is perceived in movement. What elements of the
raw movement data do you need to keep and what can you throwaway, and still keep the
personality, the emotion, the 'life' of that movement? How do you make a virtual, interactive
performance system that has its own 'materiality'?

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There is hope! Since Al Gore disclosed the inconvenient truth, the climate has changed. The time of denial is over; the era of well-informed action and sound development is with us. Sustainability has now moved from the fringe, into the mainstream of politics, society, architecture and building practice. In this new context architectural science will contribute to two main tasks: prevent further damage to our environment, and respond to challenges invoked by climate change.
The built environment and human activity within it account for a large part of the problem. Architectural science and architectural practice are part of the solution. The ANZAScA 2007 conference focuses on the solutions architectural science has to offer toward a liveable future through the following generic themes:
progress – the evaluation and improvement of built facilities, new and existing, in terms of energy intensity, financial reward and environmental impact.
practice – the relationship between our cultural heritage, new facility design, retrofit design and its realisation
through construction.
performance – the connection between building operation targets, validation of performance, and user comfort and interaction in new and existing environments.
people – the effect of space on user behaviour, user responsibility and social wealth.
In response to this challenge, architectural science researchers including students, educators, and practitioners at ANZAScA 2007, present a broad range of research activity and concern within the built environment from global issues down to the specific actions of individuals.

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A two-storey rammed earth building was built on the Thurgoona Campus of Charles Sturt University in Albury-Wodonga, Australia, in 1999. The building is novel both in the use of materials and equipment for heating and cooling. The climate at Wodonga can be characterised as hot and dry, so the challenge of providing comfortable working conditions with minimal energy consumption is considerable. This paper describes an evaluation of the building in terms of measured thermal comfort and energy use. Measurements, confirmed by a staff questionnaire, found the building was too hot in summer and too cold in winter. Comparison with another office building in the same location found that the rammed earth building used more energy for heating. The thermal performance of three offices in the rammed earth building was investigated further using simulation to predict office temperatures. Comparisons were made with measurements made over typical weeks in summer and winter. The validated model has been used to investigate key building parameters and strategies to improve the thermal comfort and reduce energy consumption in the building. Simulations showed that improvements could be made by design and control strategy changes.

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Looks at the relationship between emotional intelligence and choice theory in the work world, with particular emphasis on the implications on health and productivity. Most of us have a managing or leading role of some sort, whether at home, in community life, or at work. Also, as a professional, one can be leading through professional expertise and not necessarily because of one's place in the organizational hierarchy. There is an increasing awareness of the role of leadership and team development in organizational development, for example in health care where change is needed to manage the chronic disease burden (Dunbar et al., 2007) and utilizing and retaining a dwindling workforce (Schoo, Stagnitti, Mercer, & Dunbar, 2005). This is forcing leaders and their teams to work as smart as they can with resources that are available to them. Positive leadership has been associated with outcomes that include happy relationships, teamwork, learning, recognition, staff retention, and health and wellbeing. There is evidence that emotionally intelligent leaders in workplaces are able to bring about these positive out- comes because they are attuned to the emotions that move people around them (Goleman, Boyatzis, & McKee, 2002). In this sense, emotion can be defined as aroused energy that takes a direction (Hunt, 2004a) (Latin: e = from, movere = to move). Valerie Hunt regards emotion as the metronome of life (Hunt, 2004b). Although emotion can be a feeling state (e.g., fear, anger, joy, hate or sorrow) associated with action, its energy is, according to Hunt, directed to action, to behave(Hunt, 2004b). As mentioned in an earlier publication (Schoo, 2005), Pert (Flowers, Grubin, & Meryman-Brunner, 1993) regards emotions as a bridge that connects the mental and physical realities (p.187), and sees neuropeptides as the physical representations of these emotions. Negative thoughts and emotions such as excitement and anger have been found to increase gut motility, cancer risk and arterial plaque formation which can lead to a heart infarct (Pert, 1997), whereas positive emotions seem to do the opposite.

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The Mobile Architecture and Built Environment Laboratory (MABEL) was conceived upon the principle of investigating building environmental performance in situ. MABEL provides the first means of integrated, on-site measurement of the key aspects of internal built environments; energy, lighting, air quality, ventilation, acoustics and comfort using state-ofthe- art technology and instrumentation. The intention of this paper is to explain the how and what need to be measured in our buildings if we are to search of a genuine performance answer as well as the information to provide a solution. Several results of real building measurement are provided here, suggesting that a national program on 'as performing' is required if we are to proceed in a sustainable manner.

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In this paper we propose a Geometrically Based Single Bounce Elliptical Model (GBSBEM) for multipath components involving randomly placed scatterers in the scattering region with sensors deployed on a field. The system model assumes a cluster based wireless sensor network (WSN) which collects information from the sensors, filters and modulates the data and transmit it through a wireless channel to be collected at the receiver. We first develop a GBSBE model and based on this model we develop our channel model. Use of Smart antenna system at the receiver end, which exploits various receive diversity combining techniques like Maximal Ratio Combining (MRC), Equal Gain Combining (EGC), and Selection Combining (SC), adds novelty to this system. The performance of these techniques have been proved through matlab simulations and further ahead based on different number of antenna elements present at the receiver array, we calculate the performance of our system in terms of bit-error-rate (BER). Based on the transmission power we quantify for the energy efficiency of our communication model.

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Environmental decision making during the building design process has typically focused on improvements to operational efficiencies. Improvements to thermal performance and efficiency of appliances and systems within buildings both aim to reduce resource consumption and environmental impacts associated with the operation of buildings. Significant reductions in building energy and water consumption are possible; however often the impacts occurring across the other stages of a building‘s life are not considered or are seen as insignificant in comparison.

Previous research shows that embodied impacts (raw material extraction, processing, manufacture, transportation and construction) can be as significant as those related to building operation. There is, however, limited consistent and comprehensive information available for building designers to make informed decisions in this area. Often the information that is available is from disparate sources, which makes comparison of alternative solutions unreliable and risky. lt is also important that decisions are made from a life cycle perspective, ensuring that strategies to reduce environmental impacts from one life cycle stage do not come at the expense of an increase in overall life cycle impacts

A consistent and comprehensive framework for assessing and specifying building assemblies for enhanced environmental outcomes does not currently exist. This paper presents the initial findings of a project that aims to establish a database of the life cycle energy requirements of a broad range of construction assemblies, based on a comprehensive assessment framework. Life cycle energy requirements have been calculated for eight standard residential construction assemblies integrating an innovative embodied energy assessment technique with thermal performance simulation modelling and ranked according to their performance.

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New Zealand is one of the world’s largest producers of dairy products and has a climate with high levels of solar radiation; however, the use of solar energy in the dairy processing industry has received limited attention. An examination of historical records found that the annual peak in New Zealand milk production and processing occurs at a time when solar radiation levels are increasing markedly. An F-Chart analysis was used to simulate the performance of large-area arrays of solar collectors and to determine their suitability for heating and cooling in a dairy processing environment. For the study four types of solar collectors were analysed: glazed flat plates, evacuated tubes, evacuated tubes with CPC reflectors and a building-integrated solar collector under development at the University of Waikato (UoW). It was found that of these echnologies, both flat plate and evacuated tubes with CPC reflectors could make useful heating and cooling contributions. Furthermore, the solar fraction was determined mainly by the collector area to storage volume ratio. Finally, it was found that the UoW building-integrated solar collector could make a significant contribution to energy use in dairies and may be an attractive future technology for the industry.